I wish you'd make things clear. Topic says "totally dead" yet you say it says "insert correct sim card" so obviously it's not dead. You should have requested advice before doing things blindly. Messing around flashing GDFS without knowing what you're doing can have disasterous consequences. As I said earlier; Your phone may well have been patch unlocked and so flashing it will have removed the patch.
Provide identify log from SETool2lite.